airbob2004

Can anyone suggest how to connect two ar7000 recievers together in one air system?

alan0899

G'day Mate,
I would not connect them together at all, so, If you are using 2, it must be a good size aircraft, so I would use 2 of everything, RX's, switches, batteries, & servos to suit, just bind both RX's, at the same time, to the same model memory & they will both work together, easy.

vita-40

i allso want to connect two receivers as a back up.I understand the two batteries two switches but how would you hook up the servos?

huck1199

Non-reversing Y-harnesses?

Steve Percifield

My Feedback: (14)

It's 1 receiver for the left half of the airplane and another receiver for the right half of the airplane. DO NOT CONNECT THE 2 TOGETHER. independent battery and switches.

huck1199

Steve, what is the point of this if not redundancy?

eagledancer

the point is if one receiver goes bad you still have half the control surfaces. I.E. one receiver will control throttle, 1 aileron, 1 elev half. the other receiver will control rudder, 1 aileron (the other one) and one elev half(the other one) if one receiver dies you still have some control

Steve Percifield

My Feedback: (14)

When bigger airplanes started using 2 and 3 servos for each aileron, and 2 for the elevator, and maybe 2 or 3 for the rudder, you simply ran out of ports or outputs on a receiver. So we started using 2 receivers and dividing the plane down the middle so we would have reveiver ports without using wyes. This kept the transmitter's adjustability available for each out put. Now, we have other ways to do it, such as power expanders which give us multiple ports for each receiver output or channel, and also provide adjustability for each servo driven. So, now a lot of the guys are back to 1 receiver, but still use dual batteries and switches. So it was not done just for redundancy, which it does provide, but to give big airplanes servo outlets.

But never run a wye to connect both receivers to 1 servo. The left and right systems have to remain separate.

Although better today than in years past, the weak link is still the battery and switch. So, unless you are driving 12 servos, a safer system is to use 2 batteries, and 2 switch harnesses and 1 receiver. Just plug the extra switch and battery into any unused servo port on the receiver. Most guys will use the same capacity for the extra battery as your main pack, but testing has shown, that it really doesn't matter. You could use a smaller pack as your back up or second battery and no harm will come. I use this system on anything 1/4 scale and larger.

Also, if you are using Nicds or Nimhs, use 5 cells. It not only provides better servo performance, but also gives you the security of an extra battery cell in case one cell fails. If 1 cell dies on a 5 cell pack, you still have a 4 cell battery left to save your airplane. Checking battery voltage between flights will show the failure and save your plane.

Hope this helps
steve

Steve Percifield

My Feedback: (14)

More.......

Also, having 2 receivers and redundancy does not gurantee it will save your plane. It depends on the type of plane and the type of failure. If the left side fails and all servos are driven to their extremes, the right side will probably not have enough authority to overcome the failure, you will still crash, just with more money on board. If you are lucky enough for 1 side to just go dead or stop working, you will probably save the plane. But this would probably be a battery or power failure, which dual batteries would have saved. And if the problem is radio interference, mulitple receivers won't help.

just thinking out loud
steve

huck1199

Steve, thanks for the explanaton. Is it wise to split multiple servos accross the whole plane? Eg. 2 servos per aileron and 2 elevator servos each pair split to two receivers. Also using two batteries and switches. This would seem to give you redundancy.
Thanks

The Ghost

The main reason we went to multiple servos on the ailerons was because of the much larger size of the surface on the 1/4, 1/3 scale and did not have the high power servos of today, most larger models today you only need one servo per surface as the power of the modern servo will work it.

Cheers